All this shirt tugging and grabbing in the box is a blight on the game that has taken far too long to be punished and clamped down on, so they're all pushing the envelope as far as they can get away with.
I guess from the ref/VAR's point of view, they have to break down the situation based on where the ball is and who is likely to have the biggest effect on it. In that situation, the ball is Raya's to go for and was stopped. There's plenty of other stuff going on that's punishable but its a case of which offence is having a bigger effect on the outcome - they can't just let it all slide.
In isolation, the shirt pull from Todibo that was happening long before Pablo jumped is the foul that's stopping Raya from getting a clean attempt at the ball than Pablo jumping up with the keeper which I think he's entitled to do. The officials have to simply see the passage of play on its merits rather than any effect it has on the league table and in my view, made the right call under immense pressure.
However, I believe that players are far too quick to be whining and moaning for fouls than taking the situation into their own hands because they've got the safety net of VAR.
Keepers these days seem to be piss weak when in days gone by, a bloke like Schmeichel, Seaman, Martyn etc wipes out all and sundry to get to that ball and leaves Pablo, Todibo and the bloke sniffing his armpit in a heap. Seeing all the traffic in front of him, maybe Raya should have given himself a couple of yards to get a better run at it than get caught underneath, knowing that the ball was going to be delivered into all the bodies in front.